The Great Barrier Reef Is Critically Injured

The Great Barrier Reef Is Critically Injured


It hasn't been a great year for the Great Barrier Reef. Record-breaking sea temperatures and mass coral bleaching events have left the world's largest coral reef ecosystem invariably crippled.

For the last few thousand years, marine biota and calcium carbonate compensation systems have sustained the delicate ecosystem of the Reef. Only in the past few decades have these support systems begun to be overwhelmed. Since the Industrial Era, coalescing streams of harmful processes have been whittling away at the Reef, slowly killing the life within.


The Great Barrier Reef is home to over 600 types of coral and over 1,500 types of fish. (Source: EPA/James Cook University Australia) The Great Barrier Reef is home to over 600 types of coral and over 1,500 types of fish. (Img Source: EPA/James Cook University Australia)


So what is causing the damage? Part of the answer can be attributed to ocean acidification. The ocean absorbs 24 million tons of industrially-generated CO2 every single dayThis changes the chemistry of the water and renders it more acidic. When the waters surrounding coral become more acidic, the coral cannot absorb the calcium carbonate needed to form its protective "skeleton". Without it, the coral cannot create the habitat needed to host the microscopic, single-cell algae it depends on for food. Having no protective coating also means that the reef is less resilient to chemical or physical dangers.

The other main threat to the Great Barrier Reef that goes hand-in-hand with ocean acidification is the general increase in oceanic temperatures. Unusually warm waters can upset the delicate, symbiotic relationship between coral and its algae. Even an increase of 1 degree Celcius over four weeks can drive the algae out of the coral, leaving it a stark white. This is what is known as a coral bleaching event. Following May 2016's massive coral bleaching event - the largest in recorded history -  22% of the coral found in the Great Barrier Reef has been pronounced dead.


enfos coral great barrier reef Anatomy of a coral bleaching event. (Img Source:


Although recent headlines may be declaring that the Great Barrier Reef is dead - it isn't quite buried. Parts of it are still considered quite healthy, and some experts are experimenting with revival techniques - such as seeding new coral into the reef or injecting fresh algae into depleted regions. Time will tell if the Reef can recover sufficiently. It may need our help.

Featured image credit: NASA



Posted in Global Issues